1) Field of the Invention
The present invention relates to the attenuation of blasts and, in particular, to apparatuses and methods for attenuating blasts with a shield formed of attenuation, or absorptive, material.
2) Description of Related Art
An explosion is typically characterized by a blast or sharp increase in pressure that propagates in a wavelike manner outward from a point or area of origination. Whether intentionally or unintentionally initiated, such blasts can result in severe damage to buildings, vehicles, and personnel. For example, a blast from a bomb that is detonated in a car parked near a building can cause structural damage to the building, damage components therein, and/or injure people within the building. Similarly, ballistic and aerial explosive devices can cause costly damage to buildings and other types of structures. An explosion originating in a cargo container can rupture the container and propagate therefrom. Explosive blasts can also travel through media other than air, for example, an underwater blast that propagates to a boat, submarine, or other vessel and inflicts damage.
The use of barriers for attenuating the blasts associated with explosions is well known. For example, buildings at risk of blast damage during battle conditions are sometimes protected by walls formed of concrete, sand bags, and the like. Such dense barriers provide a protective effect to an area by deflecting and/or attenuating the blast and thereby preventing the blast from reaching the protected area or at least reducing the momentum or overpressure of the blast that does propagate to the area. In some cases, however, the blast may refract over or around the barrier and propagate into the protected area. Additionally, the construction of barrier devices can be prohibitively expensive, and such barriers can be impractical for protecting high structures, structures in densely populated regions, mobile structures, or underwater structures. Further, barriers can detract from the aesthetic appeal of a structure or area.
Thus, there exists a need for a blast attenuation device that provides an effective and space efficient shield for a protected area, including an area that includes a tall structure, a structure in a densely populated region, a mobile structure, or an underwater structure. The shield should be cost effective for construction, operation, and maintenance. Further, the shield should be adaptable to minimize the aesthetic impact of the shield or to render the shield aesthetically appealing.